The gravel, dirt and debris tore through Caroline Budinich’s body — mangling her leg and nearly severing her fingers as the out-of-control Metro-North train tore a path of destruction.

When it was over, the spunky SUNY New Paltz student was grateful to have survived, but didn’t know if she would ever overcome the physical and mental anguish.

“She’s not doing too great. She’s in a lot of pain,” her mom, Christine Duran, told The Post Monday as she sat vigil at her daughter’s St. Barnabas Hospital bedside.

“Her injuries are fairly serious. She won’t be able to walk correctly unless everything goes well. Her leg was mangled up quite a bit.’’

Caroline, 21, was heading into Manhattan to see her boyfriend when the commuter train went off the rails Sunday, her mom said.

She was carried away from the scene on a stretcher, with ruptured ligaments and parts of her dislocated leg missing so much flesh from thigh to calf that the bone was exposed.

The fingertips of Budinich’s right hand were nearly cut clean off, her mom said.

The young woman has already undergone several surgeries.

“She’s going in for another operation now because the wounds are very dirty,” Duran said. “They had to keep it open to clean it. They’ll have to put pins in and an external brace to make sure it heals properly.’’

Duran said she knows her daughter, an aspiring writer and director, is lucky to be alive, and could have faced far worse than an estimated six- to eight-week rehab.

Budinich told her mother that the train was speeding before it jumped the tracks near the Spuyten Duyvil Station.

“She said it was going too fast,’’ Duran recounted. “There was a lot of commotion. She said she heard a big bang and, all of a sudden, she noticed the train was unstable and people were going all over the place.”

Budinich was conscious as she was transported from the scene.

Photos from the rescue effort show Budinich — her right leg twisted beneath her at an unnatural angle and her right hand bandaged — looking skyward as the train’s driver, William Rockefeller, walks by, surveying the horrific scene.

Budinich was one of several crash survivors rushed to St. Barnabas. Seven remained in critical condition at the Bronx center Monday, said Dr. David Listman, while two were released.

In addition to their physical wounds, he predicted the injured riders will suffer from post-traumatic stress, particularly when it comes to getting back on a train.

“I think that’s going to be very difficult for them, honestly,” Listman said.

A total of 21 crash survivors were still being treated in area hospitals Monday.

Meanwhile, the horror of the derailment, which killed four, was marked by stories of selflessness and bravery, as shaken passengers set aside their own pain to help fellow commuters.

Celebrity pastry chef Steven Ciccone, who has cerebral palsy, emerged as a hero Monday after fellow riders recounted how he helped save Dr. Denise Williams, who suffered a spine fracture in the crash.

Williams, 55, told WCBS/Channel 2 that Ciccone found her after the crash, and refused to leave her side.

When Williams’ family arrived at NewYork Presbyterian-Columbia University Medical Center, Ciccone was still watching over her.

“I just spoke to her and held her hand, asked her what was wrong. She asked, ‘You know, could you do something for my head? Could you make it more comfortable?’ ” Ciccone recounted, from his own hospital bed.

“I was crocheting a scarf and I had a ball of yarn, so I used the ball of yarn to support underneath her neck like a pillow.”